Airport lighting device



March 2 1950 H. A. CLINE ETAL AIRPORT LIGHTIZNG DEVICE Filed Oct. 6, 1947 INVENTORS whau a 52 q ATTORNEYS Patented Mar. 21 1950 .o'ivi'rao STATES PATENT OFFICE .AIRPQR flhio, assignors, by mesne assignments, to Emarco Corporation, Chicago, 111., -a corpora.-

ttion of'lllinois App icat n O t be 1947, Seria N- 2 78,811.36

(Cl. 240w1.2)

11 Claims. 1

'This invention relates to airport lighting, and more particularly to a lighting device adapted for use in marking paths such as taxi strips on an airplane landing field.

One of the principal objects of the invention is to provide a lighting device adapted for use ,in marking taxi strips at an airport which is simple butstrong and reliable in construction, eiiicient in operation, and. which will aiford a clear and distinctive marking signal effective to designate a desired path and visible over a wide angular rangealong the path.

Another object is to proyide such a marking light which is adapted ;to Joe positioned substantially above the plane of the landing field for clear visibility but which also is so constructed as to minimize .the possibility of damage to ,an,airplane coming in contact therewith.

An additional object is to provide such a mark inglight which 'isso constructedas to be readily knocked down if struck by a .InQving airplane without injury to the plane and also without injury to the device itself.

Afurther object is to provide an airport marking light having a readily fracturable support which is constructed for readily detachable connection to the "light and to a fixed supporting baseand which can thusbe quickly and easily removed and replacedin the event of fracture as a result .of contact with thelight by a moving airplane.

Other objects and advantages ,will be apparent from the following description, the accompanyme d awin s and the ap ended cla m .In he drawin Fig.1 is a view in perspective ofa marker light for an airport taxi path constructed inaccordance with the invention;

Fi 2 sa v w in p s ect ve sh wi si h light of Fig. 1 knocked down and broken off irom its support as by being struck bya moving airplane;

Fig. 3 is a view in vertical longitudinalsection through the marker light ofFig. 1;

Fig. 4 is a fragmentary view taken in section substantially on ,the'line"fl.4 of'jFig. 3, with the gas-discharge :tube removed;

Fig. .5 is an enlarged sectional .view through the fracturable supportof thelight of Fig.1, the view being taken approximately as indicated by the lined-"5 ofFigE; and

Fig. 6 is a view similartoFigB but illustrating the iracturable support in fractured condition.

Referring to the drawing, which illustrates a preferred embodiment "of fthe present invention,

and more particularly toFigs. i -to l, the frame of *2 the light is generally triangular in outline, and it includes a base panel H) of sheet steel and an upper portion formed of a strip of sheet steel bent to provide an=inclined front panel ii, an inclined back panel 4'2 and a shorttop panel 13.

The lower ends of the front and back panels ll and"l-2 are secured as by bolting or welding to the base panel Ii]. An elongated light source is mounted in the frame and is shown as formed by a gas-discharge tube bent'back on itself at an acute an le, for example to provide an upper portion i5 and a lower portion it together Ldefining a common plane substantially perpendicular to the base panel I 0. As shown in Fig. 3, the front panel H and base panel In together form substantially the same angle asthe two tube portions 15 and i5, and each tube portion is accordingly substantially parallel to its adjacent frame panel. The -bent middle portion 11 of the tube is supported in a hole adjacent the lower end of front panel I I, a suitable grommet or washer I8 being provided for cushioning purposes as shown in Figx3.

Reflectors are provided for directing light emanating from thetube portions 15 and -l 6 laterally of the plane defined thereby on both sides of the frame. Referring-particularly to Figs. 3 and 4, there are two reflectors 20 for the "lower tube portion l6, eachformed of a strip of aluminum or other suitable sheet "metal having a V configuration in crosssection. The upper reflector 2D has its outer edges -2-| flanged and bolted or otherwise secured at '23 to a shelf portion 22 of the frame *formed' by-a -strip of sheet-metal positioned above base panel in and welded or otherwise sec ured at its opposite ends to the front panel 11 and backpanel l -2. {Ilhelower reflector 20 is inverted-with;respectto the upper reflector, and its outer edges 2| are bolted or otherwise secured at -23 to the ibasepanel 10. As shown in Fig. 4, the central edges of the two reflectors 2|] are positioned just above and below, respectively, the tube portion 16, and their surfaces adjacent the tubeslope-away therefrom at'angles such that substantially all-light emanating from the tube is reflected outwardly on both sides of the frame. suitableresults with ;respect to such directingof the lighthavebeen obtained with-the sides of the reflectors -20 forming angles of the order of 30 with thehorizontal.

A similar reflector 25 is provided between the tube portion l5 and 'the front-panel I I, this refiectorhaving similarly flanged side edges --26 bolted at 21 to the f;ron;t panel ll of-gthe frame, as shown in Figs. 1 and. 3, and having its upper surfaces similarly inclined at angles of the order of 30 to the surface of front panel The reflector thus acts to reflect light from the tube portion l5 not only laterally on both sides of the frame but also upwardly and forwardly in accordance with the angular inclination of both front panel II and the sides of reflector 25.

Referring to Figs. 3 and 4, each end of tube |5|6 is mounted in a suitable supporting clip carried by a holder 3| of insulating material bolted or otherwise secured to front panel and base panel l0, respectively. A pair of clip clamps 32 in turn provide for making the desired electric connections to clips 30 and thus to the terminals at each end of the tube. Referring to Fig. 3, wires 33 and 34 connect the clips 32 at each end of tube |5-| 6 with the proper terminals of a transformer 35, which is carried by the shelf portion 22 of the frame. Shelf 22 also supports a power factor correction condenser 36 for tube |5-|6, which is positioned adjacent transformer and connected thereto at 31 as indicated in Fig. 3.

Electric current is brought in to the transformer and tube by a pair of wires 40, which are supported in the frame by being threaded through holes in back panel l2 provided with suitable grommets 4|. One of wires 40 is connected to transformer 35 and the other to one terminal of a switch 42 mounted on the under surface of top frame panel I3. A wire 43 leads from switch 42 to one terminal of a fuse 44 mounted in a clip or bracket 45 bolted or otherwise secured to the undersurface of front panel I and another wire 46 connects the other terminal of fuse 44 to transformer 35 to complete the operating circuit for the tube. The operating pin 41 for switch 42 extends through top frame panel l3, as shown in Fig. 3, and is provided with a spring 48 acting to hold it normally in position to open the contacts of the switch.

A cover or housing 50 is provided for enclosing the frame and the tube |5-|6. Referring particularly to Figs. 1, 3 and 4, the housing 53 includes side panels 5| formed of a suitable sheet metal and front portions 52 and 53 curved generally concentrically about the axis of tube portion l5. Another sheet of metal forms the back 54 and top 55 of the housing and is welded or otherwise secured to the side portions 5| and front 5 portion 52. In order to provide adequate protection for the frame and tube if the light is struck by a moving airplane or other vehicle, it is desirable to form this housing of relatively strong and rigid material. For example, the side panels 5| and the back and top strip 5455 may be formed of 20-gage chrome steel, and the front portions 52 and 53 may be formed of lfi-gage chrome steel and welded to the side panels and top part 55. With the housing constructed as thus described and shown, and with the frame panels similarly formed of strong sheet metal, the housing and frame thus cooperate to protect the tube 5|6 and other electrical parts against injury if the device is struck by an airplane while in use.

In assembling the housing over the frame and tube, the lower edges of the housing fit firmly over the flanged side edges of the base panel Ill and are bolted thereto as indicated at 56. Also, the base panel ||l is bent upwardly at the front of the frame to form a semicircular bracket portion 51 formed for close engagement with the inner curved surface of the front of the housing, the angle between this bracket portion and the remainder of base panel I!) being such that the bracket portion 51 will be substantially perpendicular to the axis of curvature of the front of the housing as shown in Fig. 3. The top 55 of the housing is arranged at such angle as to be substantially parallel to the top panel |3 of the frame, as shown in Fig. 3, and thus to engage and depress the switch pin 41 against its spring $8 to a position closing the contacts of switch 42. Thus when the housing 50 is in place enclosing the frame, the circuit through the tube will be closed, but the circuit will open when the housing is removed, as for servicing the device. A handle 58 may be bolted or otherwise secured to the top 55 for ready manipulation of the housing.

The housing 5!] is provided with light transmitting windows overlying the tube portions l5 and i6 and arranged to transmit the light from these tube portions and reflected by the reflectors 23 and 25. As shown, one window 6|] is formed of a sheet of suitably strong transparent material which will not splinter if broken, such as tempered glass, methyl methacrylate or other safety glass material curved substantially concentrically with the tube portion |5. The front of the housing 5|! is cut away to receive this window, which is mounted therein by means of a channel iii of rubber or other suitable material as best seen in Fig. 3. This window 6|] extends at either side of the housing substantially to the lower level of the reflector 25 and thus provides for transmitting substantially all of the light emitted from the tube portion l5. Windows 62 of similar transparent material are provided at either side of the housing and are arranged in line with the tube portion l6. Each of these windows 62 is generally oblong in shape, and each is similarly mounted in a suitable hole in the side 5| of the housing by means of a rubber channel 63 as shown in Fig. 4. Each of these windows 62 thus serves to transmit laterally of the housing the light emanating from the tube portion l6 and reflected by the two reflectors 23.

A support is provided for mounting the light with the tube portions I5 and I6 and the windows as and 52 in marking relation to an airport path, and this support includes a readily fracturable joint such that it will be fractured if the upper part of the light is struck by a moving airplane, thus avoiding damage both to the plane and to the upper part of the light itself. Referring particularly to Figs. 3, 5 and 6 the fracturable joint includes an upper portion ill, a lower portion H and an intermediate connecting portion 12 formed by a relatively deep peripheral groove 13 in the outer surface of the joint. The upper end M of the upper joint portion 10 is tapered and telescopes into a complementary socket portion of a plate 15 bolted or otherwise secured to the base panel ID of the light frame. The lower end 16 of the lower joint portion 1| is threaded for mounting in a support such as a standard pipe flange 11, which may be bolted or otherwise secured to a fixed base such as a cement block 78 as indicated in Fig. 1.

The groove 13 in the fracturable joint is formed to a depth such that'the intermediate joint portion 'i2 will be of substantially lesser strength than the upper and lower joint portions ill and ll, so that when a bending moment is applied to the joint it will readily break at this portion l2. Also, the joint is made of a less strong material than housing 5!] and the frame, such as aluminum, so that its intermediate portion 12 is of lesser strength than the housing 5|), with the atomam willaalso' bennderstoodsas already pointed ioutlllfl thatsthe: panels of; the fr'ame reinfdrcerathe house-- i ingsagainst: damage :from an :externalzblow and thus facilitate;.transmissionlofr.theiforcer ofr'suoha blow to the fracturable portion:ofthejointirather; than absorbing this .sforce;;withinathez.light strum tore-itself;

The fracturable-isupport :also a carrieszfthe elec trical connections: to anrloutside source'- of operat-e ingicurrentifor 'the transformerefi :and the tube==. 54-48.; Relierring -toicl igs. 5 'fand 6; these elec' tricaliconnections areprovi'dedsby complementary plug and 1 socket l members: .8 and 8 l-, resp'ectit ely; the. plug. 8B1receiving"theuloweri'end of the wires 49. and .thecsockett. 8 if having a: cable 8'2 leading therefrom: to. an outside'source' of "lcurrentl 'As" shown 1 in Fig. 5, the: plug Y 8fl iscmounted within L the upper. :joint p0rti0n ='|ll", -and the socket 8l is secured: Within; the. lower 1 joint portion 1 l thew socket including. a collarca whichis removably secured withinthis portion of. the joint: by means: of 'a set screw-86.- A screw clamp fll is mounted on. the. wires .40-:adjacent:1t0 theaplugflflfito reinforce' the interconnection ofuthd-plug Hollands the Wires 40;...

Withithis=oonstruction, when the lig-ht is struck arsoumerof: white r1ight;.-with the resulting loss of light:byirabsorptlonainithe filter. i It. wiflialSG Jbe seenzithat: the'lights of; the inven tion tcamsbeitmourite'd; aniiappreciable distance abovef-zthewplane aromthez field; imposition to: be

readily visible from the pilots seat even'after the; tail-i 'oftz'th planei is'ilon the ground" with the usualldifliculty fiin. ivisionz withurespect. to ground v objectsicloselyl inniront sot the plane. Fur-therinore','-.1theuinteriona constmictionicf the light as descrioeduis such tasstosrminimize the possibility ofufdama'gektd the fllght itself as a result of being thus: str.uck:...and knocked down; and the light maybe quickly and "easlly' set' up againwith rela atiirelyrlittleraeiiortr "andi-withxthe only" new part neededw. being-:thetsimple and easilyreplaced fracturable tjointxwhich mounts the light above its;: ermanentisupporting bases Whiie thersfornuofapparatus:herein described constitutes a preferrecl embodiment of-th'e invention; iti 'is to .be'%unclerstood*that: the inventionis notwlimite'd tdrthis preciseform" of apparatus; andsthat changes may be made the-rein without 1 departing fromzr the L scope "of the' *invention and the purviewof-"the appended claims."

What is claimed lsz' 1,31 Arimarker lighting unit of' the oharacter described ircomprisingaframeymeans supported by saidzifiiameiforming an elongated light source in- I cludingstwo r relatively i inclined portions together deflningiman acute angle; means *for supporting i said. frQJInB With OHBLOf'. said light source portions lying:inraisubstantiallyhorizontal lplanex andnvithl thGLOtIICILDf said lightsourc'e portionsinclined up ward'ly :1: withiirespect' s to said s ifirst named light source-portion, :aehousingfifor said frame andxlight sourcesmeansx forming atwindovsrin said housing: overlying saidarinclinedolightl. source portion: and inl-xpositionito. transmit lightatheirefrom .over'a substantialaangular. range forwardlypof. said. unit,

andxmeans forming :an additional: window in the i side: otisaid housing-arranged :to transmit. light.

parts of the: .joint. and removing these. broken joint parts, mounting a new joint on the sup-- porting. base. and: securing "the socket" therein, and. then. connectingstheplug to the socket. and ereotingmtherlightagain byfittlng-the socket portion of; its "base plate 15 down oventhe tapered uppertend 14 of. thewnew jointr- Inuse, a plu'ralityof these "marker lights mayher mounted along an airplane path with thelower tub'e portionr'lfi ofeach light horizontal and zsubstantially perpendicula'r to thellength of the path andwith 'the tube portion I5' and"Win dowfili ifacing the path. With this arrangement; thelight will form a distinctive signal having at a distance the-appearance 'ofanarrow"head poi-ntingtoward the path; and this signal WillibE' Visible for a substantial rangealongthe path. Thus with the lights arranged in pairs on op;- posite sides of apath, thexresultingarrow-like. signals willappear to "point towardthetproperfl direction to be followed by a taxiing airplaneand.v

other. distinctive. color. In this way substantially all -the. emitted light. can .be utilizedwfor. markings purposes, instead ofemploying acoioredfilten and from. the other. oflsaid light' source portions laterally ofisaid unit;

2... A marker: lightingauniti of .thepharacter. described-.icomprisingi1a frame having... a generally i triangulaimoutline, meansforming; 1 an elongated light source including: two. portions inclined at with respect-to each I other. at: anzacute angle and: to-- gather x defining. a a common plane,-': means for. mounting said light-source portions insaid frame with eachnsaidtportion: substantially parallel-to. vonewsidelsof saidi.triangular-1 outline; means for. supporting said :frame :Witlr said plane .substan tia1lyyvertical,-.aihousingrfonsaid frame and light source-,omeansi forming- ;windows in .said..housing in position to=transmit1ight from said lightzsou-rce portionslforwardlyqand laterally .cf saidunit and at. lbotha-sidem thereof, and x reflector means arranged :to project ilight from saidlight source lat eral-lyvotlsaidiframe andithroug h said light 'transsmitting portions of said housing.

3. .A. marker. lighting limit of the characterzdes scribedcomprising a .base, :a frame supported on ;sa-idebase ,i means supported .by said frame f0rmins. amelongated-ilighti source including a portion substantially parallel':l-to said base'and. another portionipositioned: at: the-front of saidxframe and. inclined-mpwardly at an acute angle to-saidfirst named. portion; a .housings.-enc1osin said. frame andlightsouroeg meansiformingta; swindow at the front oi saidlhousingoverlying saidinclined light. source: portion:.and in position .to..itrans1nit light therefrom-inwardly;andirlateraliy over: a sub;

:stantial angular range, means formingi zadditional 7 windows in each side ofsaid housing in position to transmit light from said first named light source portion at both sidesof said unit, and reflectors supported by said frame in position to direet light from said light source portions through said windows. 7

4. A marker lighting unitof the character described comprising a plurality of .panels of sheet material arranged to form a generally triangular frame of substantially greater height and length than width, means for securing said panels together with each said panel substantially perpendicular to a plane defined by the height and length of said frame, means forming an elongated light source including two portions inclined at an acute angle to each other; means for supporting said light source in said frame with each said portion thereof substantially parallel to one of said panels, a housing of substantially the same general shape as said frame adapted to enclose said frame and light source with said panels cooperating to brace said housing against inward deflection, and means formin windows in said housing arranged to transmit light from said light source laterally at both sides of said housing and forwardly from said housing.

5. A marker lighting unit of the character described comprising a base, a frame supported on said base and including front and rear panels inclined upwardly from said base and inwardly toward each other, a shelf secured to said front and rear panels in upwardly spaced relation with said base, a gas-discharge tube supported by said frame and including a portion substantially parallel to said base and a portion at the front of said frame inclined at an angle tosaid base and substantially parallel to said front frame panel, a transformer and a condenser for said tube mounted on said shelf, a housing enclosing said frame and tube, means forming a window at the front of said housing overlying said inclined tube portion and in position to transmit light therefrom over a substantial angular range, means forming additional windows at either side of said housing in position to transmit lightfrom said first named tube portion laterally on both sides of said unit, a reflector having in cross-section an inverted V configuration mounted on said basev in position to reflect light from said first named tube portion through said side windows of said housing, and a similar reflector secured to said front panel in position to reflect light from said inclined tube portion through said front window.

6. A marker lighting unit of the character described comprising a frame, means supported by said frame forming an elongated light source including two relatively inclined portions together defining an acute angle, means for supporting said frame with oneof said light source portions lying in a substantially horizontal plane and with the other of said light source portions inclined upwardly with respect to said first named light source portion, means for supporting said frame in marking relation to an airport path, said sup porting means including a portion adapted for ready fracture if said unit is struck by a moving airplane, a housing for said frame and light source, means forming a window'in said housing 7. A marker lighting unit ofi'the character described comprising a base, a frame supported on said base and including, front and rear panels inclined upwardly from said base and inwardly toward each other, a shelf secured to said front and rear panels in upwardly spaced relation with said base, a gas-discharge tube supported by said frame and including a portion substantially parallel to said base and a portion at the front of said frame inclined at an angle to said base and substantially parallel to said front frame panel, a transformer and a condenser for said tube mounted on said shelf, a housing enclosing said frame and tube, means forming a window at the front of said housing overlying said inclined tube portion, means forming windows at either side of said housing in position to transmit light from said first named tube portion laterally of said unit, a reflector having in cross-section an inverted V configuration mounted on said base in position to reflect light from said first named tube portion through said side windows of said housing, a similar reflector secured to said front panel in position to reflect light from said inclined tube portion through said front window, means for supporting said light in marking relation to an airport path, said supporting means including areadily fracturable portion adapted to be broken off if said housing is struck by a moving airplane, and means in said supporting means for connecting said tube and transformer to a source of operating current, said connecting means including relatively detachable complementary connector members arranged to be automatically disconnected from each other in the event of fracture of said supporting means.

8. A marker lighting unit of the character described comprising a base, a frame supported on said base and including front and rear panels inclined upwardly from said base and inwardly toward each other, a shelf secured to said front and rear panels in upwardly spaced relation with said base, a gas-discharge tube supported by said frame and including a portion adjacent said base and a portion at thefront of said frame inclined at an angle to said base and adjacent said front frame panel, a transformer and a condenser for said tube mounted on said shelf, a housing enclosing said frame and tube, means forming windows in said housing arranged to transmit light emanating from said tube forwardly and laterally on both sides of said unit, a tubular member for supporting said unit in marking relation to an airport path, said tubular member including upper and lower portions and an, intermediate portion of substantially weaker construction than said upper and lower portions for ready fracture upon the application of a bending moment, means for conducting electric current to said light source including cooperating plug and socket members, means for securing said plug member in said upper tubular member portion, and means for securing said socket member in said lower tubular member portion to provide for ready separation of said plug and socket upon fracture of said tubular member at said intermediate portion thereof.

9. A marker lighting unit for airport runways, and the like, said unit comprising a frame having a front and bottom portion, a gas-discharge tube mounted on and supported by said frame, said tube comprisingone portion extending upwardly adjacent said front of said frame and another portion extending'rearwardly therefrom, -a housing enclosing said frame and tube, means forming windows in said housing arranged to transmit light emanating from said other portion of said tube laterally on both sides of said unit, and means forming a window in said housing disposed in front of and at the sides of said one portion of said tube for transmitting light emanating from said one portion of said tube forwardly and laterally of said unit.

10. A marker lighting unit for airport runways, and the like, said unit comprising a frame having a front and bottom portion, a gas-discharge tube mounted on and supported by said frame, said tube comprising one portion extending upwardly adjacent said front of said frame and another portion extending rearwardly therefrom, a housing enclosing said frame and tube, means forming windows in said housing arranged to transmit light emanating from said tube forwardly and laterally on both sides of said unit, and V- shaped reflector means mounted in said housing adjacent said portions of said tube with the apexes thereof directed toward said portions to reflect light from said tube portions outwardly through said windows.

11. A marker lighting unit for airport runways, and the like, said unit comprising a supporting frame having a front portion, a gas-discharge tube mounted on said frame, said tube comprising one portion disposed in substantially horizontal position and extending rearwardly from said front portion of said frame, and another portin extending upwardly from said one portion adjacent said front portion of said frame, a housing enclosing said frame and tube, means forming windows in said housing arranged to transmit light emanating from said one portion of said tube laterally on both sides of said unit,

means forming a window in said housing forwardly of said frame and extending across the front and the two adjacent longitudinal sides of said other portion of said tube in a manner for transmitting light emanating from said other portion of said tube forwardly and laterally of saidunit, and V-shaped reflector means mounted in said housing adjacent said portions of said tube with the apexes thereof directed toward said tube to reflect light from said one tube portion outwardly through said first mentioned windows laterally of said unit, and to reflect light from said other tube portion outwardly through said second mentioned window forwardly and laterally of said unit.

HAROLD A. CLINE.

EUGENE C. BRIGGS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

